Atlantic Hurricane-Force Storms: Identifying Stratospheric Air Intrusions

and the Effects of Hurricane-Force Wind Events on the Iceberg Limit

Kristina Mazur1, Michael Folmer2,3, Joseph Phillips3, Joseph Sienkiewicz3, Emily Berndt4

1 NCEP Summer Internship Program, Ocean Prediction Center, 2 Cooperative Institute for Climate and Satellites, Maryland, 3 NOAA National Weather Service, Ocean Prediction Center, 4 NASA Short-term Prediction Research and Transition

Introduction During the winter and early spring months, rapidly intensifying hurricane-force storms are common in the North Atlantic Ocean. On average, there are approximately 45 hurricane-force storms per season in the North Atlantic. The National Weather Service’s Ocean Prediction Center (OPC) is responsible for providing accurate and timely warnings and forecasts, which help prevent loss of life and property at sea. Since gathering data over the ocean is challenging due to the lack of observations, satellite imagery is an important and necessary forecast tool. Improving the lead time of hazardous weather conditions is crucial to many maritime industries; therefore, identifying the probable signs of explosive cyclogenesis early on is a vital goal.

Objectives

To identify stratospheric intrusions, various satellite imagery and products were used to analyze the precursors of explosive cyclogenesis.

• Air Mass RGB and water vapor imagery from METEOSAT-10, GOES-16 & GOES-13

• Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on the Aqua and Terra satellite

• Ozone anomaly data from the Infrared Atmospheric Sounding Interferometer (IASI) on MetOp-A and –B

• NOAA Unique Combined Atmospheric Profiles (NUCAPS) from the Suomi-National Polar Partnership (S-NPP) satellite

• Scatterometer wind data from ASCAT-A and -B on MetOp-A and -B To confirm the expansion of the iceberg limit, surface current magnitude and direction and ice drift were analyzed.

• Arctic Cap Model • Hybrid Coordinate Ocean Model (HYCOM)

Data & Methods

Results

Conclusion

Acknowledgements

Provide improved and more confident forecasts for hurricane-force storms (winds ≥64 kts) and rapidly developing cyclones.

• Identify stratospheric air intrusions which could lead to hurricane-force wind events and explosive cyclogenesis.

• Recognize the impacts of hurricane-force storms on the iceberg limit.

Color Wavelengths (μm) Description

Red 6.2 – 7.3 Warming (drying)

Green 9.7-10.8 Tropical air mass & high tropopause

Blue 6.2i More moisture in a “cooler” environment

27 March 2017 Hurricane-Force Storm

31 March 2017 Hurricane-Force Storm

GOES-16 6.2 μm water vapor imagery from 1800 UTC, 25 March 2017

• Dry air that will eventually enter the March 27th storm

NUCAPS O3 anomaly imagery from 1600 UTC, 27 March 2017

• Higher than normal ozone values

Hurricane Force Winds

Impacts of the March 27th & March 31st Storms

METEOSAT-10 10.8 μm infrared imagery from 1200 UTC, 31 March 2017

• Bent-back front

MetOp-A ASCAT-A scatterometer wind data & METEOSAT-10 10.8 μm infrared imagery from 1830 UTC, 31 March 2017

• Storm force winds only captured by ASCAT-A

METEOSAT-10 Air Mass RGB imagery from 1000 UTC, 30 March 2017

• Two systems merging together • Dry air entering both systems

NUCAPS O3 anomaly imagery from 1600 UTC, 31 March 2017

• Higher than normal ozone values

METEOSAT-10 10.8 μm infrared imagery from 1200 UTC, 27 March 2017

• Bent-back front • Second low pressure system blocking

MetOp-A ASCAT-A scatterometer wind data & METEOSAT-10 10.8 μm infrared imagery from 1815 UTC, 27 March 2017

• Hurricane force winds between 64-74 kts

Identifying stratospheric intrusions in early stages of extratropical cyclone development is beneficial when forecasting hazardous conditions. This can lead to improved and more confident forecasts, and offer more lead time to those trying to avoid damaging winds and waves at sea. In addition, identifying what storm characteristics can cause significant iceberg expansion can be useful to the maritime industry. This can also provide more lead time when rerouting shipping tracks to avoid collisions with icebergs.

Wavelengths and color descriptions of the Air mass RGB product.

Special thanks to Michael Folmer, Joseph Phillips, Joseph Sienkiewicz and others at the OPC for their help and guidance. Thanks also to Genene Fisher, Bill Lapenta, and Ashley Burrell for directing and organizing the NCEP Summer Internship Program.

(Courtesy of Robert Daniels)

References Berndt, Emily B., Bradley T. Zavodsky, and Michael J. Folmer., Development and Application of Atmospheric Infrared Sounder Ozone Retrieval Products for Operational Meteorology. IEEE Transactions on Geoscience and Remote Sensing, 54, 958-67. doi: 10.1109/tgrs.2015.2471259 Bithell, M., L. J. Gray, and B. D. Cox, 1999: A Three-Dimensional View of the Evolution of Midlatitude Stratospheric Intrusions. Journal of the Atmospheric Sciences, 56, 673-88. doi: 10.1175/1520 0469(1999)056<0673:atdvot>2.0.co;2 Browning, K. A., 2004: The sting at the end of the tail: Damaging winds associated with extratropical cyclones. Quarterly Journal of the Royal Meteorological Society, 130, 375-99. doi: 10.1256/qj.02.143 NOAA National Center for Environmental Prediction, Ocean Predication Center. 2017 OPC Informational Flyer. www.opc.ncep.noaa.gov/OPC_Flyer.pdf Schultz, David M., and Joseph M. Sienkiewicz., 2013: Using Frontogenesis to Identify Sting Jets in Extratropical Cyclones. Weather and Forecasting, 28, 603-13. doi: 10.1175/waf-d-1200126.1 Zavodsky, Bradley, Andrew Molthan, and Michael Folmer., 2013: Multispectral imagery for detecting stratospheric air intrusions associated with mid-latitude cyclones. Journal of Operational Meteorology, 1, 71- 83. doi:10.15191/nwajom.2013.0107

According to the North American Ice Service (NAIS), significant expansion of the iceberg limit occurred on 29 March 2017 and 03 April 2017, just a few days after two powerful hurricane-force storms passed over the area containing the icebergs

The Arctic Cap Model shows an increase in the magnitude of a southeasterly ice drift during the period of hurricane-force winds.

The most dramatic day of significant expansion occurred on March 29th. The extent of significant expansion is dependent on the strength, duration and location of winds.

When looking at Air Mass RGB imagery, red/orange shading represents a warm (dry) air mass in the upper troposphere. If this warm (dry) air also exhibits 125% above normal ozone values it can be considered stratospheric air.

Ozone anomaly color bar (Courtesy of Kelsey Malloy)

(i = inverted)